Campanula alliariifolia (Cornish bellflower) — Clump-forming, mat-forming or upright depending on species

Overview

Campanula alliariifolia is a clump-forming, mat-forming or upright depending on species perennial in the genus Campanula, part of the Campanulaceae family, with deciduous or semi-evergreen; basal rosettes of rounded or heart-shaped leaves, narrower up the stem foliage. It typically grows around 0.7 m tall. Campanula alliariifolia grows best in full sun to partial shade, and tolerates loam and chalk or sand; most tolerate poor soils soils and neutral to alkaline pH. Its UK hardiness is rated H5-H7. Suggested uses include rock gardens, borders and alpine gardens. It is native to Turkey to Caucasus.

About

Campanula alliariifolia is a clump-forming perennial in the bellflower family with nodding, bell-shaped flowers and a basal rosette of rounded leaves. It reaches about 0.7 m and tolerates full sun to partial shade. The plant suits neutral to alkaline soils and prefers moist but well-drained conditions. Flowering occurs June to September.

Wikipedia contributors, CC BY-SA 4.0 — Campanula alliariifolia

About the genus

Campanula is the type genus of the Campanulaceae family of flowering plants. Campanula are commonly known as bellflowers and take both their common and scientific names from the bell-shaped flowers—campanula is Latin for "little bell".

Wikipedia contributors, "Campanula", CC BY-SA 4.0 — Campanula

In the garden

Campanula alliariifolia is a perennial bellflower native to Turkey and the Caucasus, grown for its hanging, tubular bells and basal rosettes of rounded to heart-shaped leaves. Plants form clumps that typically reach around 0.7 m and will tolerate either exposed sites or sheltered corners of the garden. Flowering takes place from June to September. Position the Cornish bellflower in full sun or partial shade on loam, chalk or sandy soils; it will tolerate poorer soils provided drainage is adequate. Soil should be neutral to alkaline, and the species prefers moist but well-drained conditions — alpine-bred forms will need sharper drainage. It is winter-hardy across a UK range from hardy (H5) to fully hardy (H7), so it suits most mainland gardens. Use Campanula alliariifolia in rock gardens, alpine beds and mixed borders where its low clumps and nodding flowers can spill over gravel or edge pathways. Plant with other neutral-to-alkaline lovers and avoid deep shade. The grey-haired basal rosettes emerge early in the season and remain a structural feature beneath the white bells that open from June to September.

Growing conditions

Best soil and position for Campanula

Sunlight: Full sun to partial shade
Soil type: Loam, chalk or sand; most tolerate poor soils
Soil pH: Neutral to alkaline
Soil moisture: Moist but well drained; alpine kinds need sharp drainage
Aspect: Any except deep shade
Exposure: Exposed or sheltered
UK hardiness: H5-H7

Plant details

Campanula alliariifolia size, habit and characteristics

Plant type: Perennial
Habit: Clump-forming, mat-forming or upright depending on species
Foliage: Deciduous or semi-evergreen; basal rosettes of rounded or heart-shaped leaves, narrower up the stem
Height: 0.7 m
Suggested uses: Rock gardens, borders, alpine gardens
Native to: Turkey to Caucasus

Care notes

Pruning and caring for Campanula alliariifolia

Cultivation: Undemanding given drainage and a reasonably open position. The taller border kinds are worth supporting early, since heavy rain will flatten a flowering stem and it will not lift again. Deadheading extends the season considerably, and the vigorous spreading species are best sited where they can run without swamping smaller neighbours.
Pruning: Cut flowered stems back to basal growth to encourage a second, lighter flush. Tidy remaining foliage in late autumn, or leave the rosettes intact over winter on alpine kinds.
Propagation: Divide in spring or autumn, and take basal cuttings in spring for named cultivars. Species come readily from seed sown fresh, and several self-sow where conditions suit.
Pest resistance: Slugs and snails are the real problem, particularly on emerging spring growth and on alpine rosettes.
Disease resistance: Generally healthy; rust and powdery mildew appear on crowded or drought-stressed plants.

Frequently asked questions

How do I grow Campanula alliariifolia?

Undemanding given drainage and a reasonably open position. The taller border kinds are worth supporting early, since heavy rain will flatten a flowering stem and it will not lift again. Deadheading extends the season considerably, and the vigorous spreading species are best sited where they can run without swamping smaller neighbours.

Where is the best place to plant Campanula alliariifolia?

Campanula alliariifolia prefers full sun to partial shade. It suits exposed or sheltered positions.

What soil does Campanula alliariifolia need?

Campanula alliariifolia grows best in loam and chalk or sand; most tolerate poor soils soil. It prefers neutral to alkaline soil. Aim for soil that stays moist but well drained; alpine kinds need sharp drainage.

How do I prune Campanula alliariifolia?

Cut flowered stems back to basal growth to encourage a second, lighter flush. Tidy remaining foliage in late autumn, or leave the rosettes intact over winter on alpine kinds.

How big does Campanula alliariifolia grow?

Campanula alliariifolia reaches a height of 0.7 m.

Is Campanula alliariifolia hardy in the UK?

Campanula alliariifolia has an RHS hardiness rating of H5, meaning it is hardy in most of the UK, tolerating -15 to -10°C.

How do I propagate Campanula alliariifolia?

Divide in spring or autumn, and take basal cuttings in spring for named cultivars. Species come readily from seed sown fresh, and several self-sow where conditions suit.

More in the Campanula genus

Browse all Campanula →